Flossie Wong-Staal (黃以靜 pinyin: Huáng Yǐ jìng, born August 27, 1947), born Yee Ching Wong, is a Chinese-American virologist and molecular biologist. She was the first scientist to clone HIV and determine the function of its genes, a major step in proving that HIV is the cause of AIDS. From 1990 to 2002, she held the Florence Riford Chair in AIDS Research at the University of California at San Diego (UCSD). She was co-founder and, after retiring from UCSD, Chief Scientific Officer of Immusol, which was renamed iTherX Pharmaceuticals in 2007 when it transitioned to a drug development company focused on hepatitis C, and where she remains Chief Scientific Officer.[1]

In 1972, following the receipt of her PhD, Wong-Staal undertook postdoctoral research at UCSD. Her postdoctoral work continued under 1974, when she left to work for Robert Gallo at the National Cancer Institute (NCI). At the institute, Wong-Staal began her research into retroviruses.[2]

In 1983, Wong-Staal, Gallo and her team of NCI scientists identified HIV as the cause of AIDS, simultaneously with Luc Montagnier. Two years later, Wong-Staal cloned HIV and then completed genetic mapping of the virus. The genetic mapping made it possible to develop HIV tests.[3]

In 1990, Wong-Staal moved from NCI to UCSD. Wong-Staal continued her research into HIV and AIDS at UCSD. In 1994 she was named as chairman of UCSD's newly created Center for AIDS Research.[4] In that same year, Wong-Staal was elected to the Institute of Medicine of the U.S. National Academies.

In the 1990s, Wong-Staal's research focused on gene therapy, using a ribozyme "molecular knife" to repress HIV in stem cells. The protocol she developed was the second to be funded by the United States government.

In 2002, Wong-Staal retired from UCSD and now holds the title of Professor Emerita. She then joined Immusol, a biopharmaceutical company that she co-founded while she was at UCSD, as Chief Scientific Officer. Recognizing the need for improved drugs for hepatitis C (HCV), she transitioned Immusol to an HCV therapeutics focus and renamed it iTherX Pharmaceuticals to reflect this. That same year, Discover named Wong-Staal one of the fifty most extraordinary women scientists.[1] Wong-Staal remains as a Research Professor of Medicine at UCSD.[5]